Traditionally, tankers used to transport liquefied natural gas (LNG) are off-loaded in protected waters. Once reaching their destination, these LNG tankers are typically moored alongside a quay where the connection of a quay-mounted articulated steel loading arm to the LNG tanker begins the off-loading process of the LNG.
From a safety, efficiency, and cost standpoint, it would be desirable to both off-load the LNG and transform the LNG from a liquid state to a gaseous state at an offshore location; that is, away from protected waters. The natural gas, having now been transformed from a liquid state into a gaseous state, is then readily transportable by an existing natural gas transportation system, such as through undersea pipelines as exist off the coast of the U.S., to an onshore location for temporary storage, further transport inland, processing, and/or use. Despite the increasing use and growing demand for natural gas in response to the escalating cost of oil, and the fact that the volume of natural gas being transported into the U.S. increases the need for an offshore off-loading and regasification system, no commercially viable system for the offshore off-loading and gasification of LNG in unprotected waters is presently available.
Accordingly, a need remains in the art for a system and method which allows conventional LNG tanker vessels of any size or configuration to first moor at an offshore location away from unprotected waters and then discharge their cargo of liquefied natural gas, in its liquefied state, to a regasification plant. Once the LNG has been off-loaded from the tanker vessel, the LNG tanker vessel is then made ready to depart en route to pick up another load of LNG.